Best 8K Series Grade 1 Cylindrical Knob Lock



Details: Best 8K Series Grade 1 Cylindrical Knob Lock


This Grade 1 heavy-duty cylindrical lock provides the security you count on from BEST. Unlike other cylindrical knob sets that are made from weaker metals, the BEST 8K Series is constructed of steel or brass to ensure the overall strength and durability of the lock. Plus, the knob itself is a single-machined unit—instead of being formed from multiple parts and then pressed and joined into a single unit—to provide more structural integrity and greater resistance against wear-and-tear. The 8K Series, which offers quick, economical rekeying with the BEST original interchangeable core, is commonly used in government and military facilities.


  • Quick, economical rekeying with the BEST® interchangeable core.
  • Knobs machined from brass or bronze bar stock.*
  • Rotating knob face provides for easy hand of door change without removing the knob.
  • No keeper hole on keyed knobs for added security.
  • Keyed knob removable only after the core is removed.
  • The tactile or knurled knob feature designed for blind, safety and accessibility applications.
  • Friction insert inside rose resists loosening.
  • The optional breakaway feature prevents the lockset from being overpowered by a wrench.
  • 9⁄16" throw, deadlocking latch.
  • Spin free knob feature permits the lock to be operated only by use of a key.
  • Steel retractor with low friction bearings for smooth, wear resistant operation.
  • Long bearing length in chassis for smooth, wear resistant operation.


Internal parts are brass or corrosion-treated steel
2 1⁄16" diameter to fit 2 1⁄8" hole in door
2 3⁄4" standard, 3 3⁄4" and 5" available
9⁄16" throw. Front 2 1⁄4 × 11⁄8" beveled. Latch housing fits 1" hole in edge of door
Knobs: Diameter— 2 1⁄8" ; Projection from door— 2 7⁄8" #4, #6 Knob Material
Machined from solid brass or bronze
All roses are brass or bronze reinforced with steel liner. Roses are threaded to chassis. "A"— round, 3 3⁄8" diameter; "C"— round, 2 9⁄16" diameter; "D"— convex round, 3 3⁄8" diameter "E"— special trim for 2 1⁄8" to 3" thick doors
Door Thickness
Adjustable from 1 3⁄8" to 2" standard. Special "E" trim for 2 1⁄8" to 3" doors available. The "B" style square trim is for doors 1 3⁄4" to 2" only
(STK) — 2 3⁄4" × 1 1⁄8" with curved lip and box standard (ANSI A115.3), (S3) — 4 7⁄8" × 1 1⁄4" with curved lip and box available (ANSI A115.2), (S3-7⁄8) — Conforms to ANSI A115.2 for 1 3⁄4" doors.(4 7⁄8" × 1 7⁄8" flat)
Latch & Strike Screws
(STK) Strike Package — (1) 2 3⁄4" Strike plate, (4) #8-32 / #8-16 × 3⁄4" Phillips flat head screws. 8KS3 Strike Package —(1) 4 7⁄8" Strike plate, (2) #8-32 / #8-16 × 3⁄4" Phillips flat head screws, (2) #12-24 / #12-12 × 3⁄4" Phillips flat head screws

Available Model Numbers and Combinations

Model/SKU Attributes
8K5 7R690 5", Classroom, Oxidized Satin Bronze
8K5 7R 626AM 5", Classroom, Satin Chrome (Antimicrobial)
8K3 7C619 2-3/4", Corridor, Satin Nickel
8K5 7R606 5", Classroom, Satin Brass
8K5 7R612 5", Classroom, Satin Bronze
8K3 7C605 2-3/4", Corridor, Bright Brass
8K5 7R619 5", Classroom, Satin Nickel
8K5 7R605 5", Classroom, Bright Brass
8K5 7R611 5", Classroom, Bright Bronze
8K3 7C611 2-3/4", Corridor, Bright Bronze
8K5 7R625 5", Classroom, Bright Chrome
8K3 7C625 2-3/4", Corridor, Bright Chrome
8K5 7T626 5", Dormitory, Satin Chrome
8K5 7T690 5", Dormitory, Oxidized Satin Bronze
8K5 7T 626AM 5", Dormitory, Satin Chrome (Antimicrobial)

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